Status, threats and conservation challenges to key aquatic fauna (Crocodile and Dolphin) in National Chambal Sanctuary, India

The Chambal River in India supports a rich variety of fauna and flora including the endangered Ganges River Dolphin and Crocodile. Threats to the continued functioning of the Chambal River as a living system have reached a critical level due to the exponential expansion of human populations. Population status of Crocodiles and Dolphins in a 425 km stretch of the Chambal River was determined by surveys conducted every year during 2007 to 2010. The average number of Dolphins recorded during the surveys was 82.75 ± 09.1 yr⁻¹ with an encounter rate of 0.19 km⁻¹ (range 69–91), Gharial 916.25 ± 91.6 yr⁻¹ with an encounter rate of 2.15 km⁻¹ (range 870–996), and Mugger 235 ± 27.7 yr⁻¹ with an encounter rate of 0.56 km⁻¹ (range 194–301). Increasing demands for sand for development activities and water abstraction for irrigation and energy generation, coupled with mortality in fishing nets, are likely to affect these populations. Recommendations for management and research are made to ensure the effective conservation of these species in the Chambal River.